12
4-4.3. ALARM MONITORING AND CONTROL
In the amplifier, all normal variations are automatically compensated for by the
spurious detector control. However, when large variations occur beyond the
adjustment range of the loop control, a loop fault will occur. The alarms are output
via an 18-pin Molex connector on the module for subsequent remote monitoring.
4-4.4. SPURIOUS EMISSION DETECTION DSP CIRCUIT
The primary function of the spurious detection circuit is to monitor the spurious
emissions mask of the RF signal at all amplifier stages. DSP circuitry is used to
control the phase, gain, and bias of all amplifier stages, thereby optimizing the
spurious emissions mask of the CDMA output signal.
4-5. AMPLIFIER MODULE COOLING
Each amplifier module is contained within a thermally conductive chassis which,
when properly mounted on an adequate thermal surface, will provide sufficient
cooling to maintain the amplifier within the specified operating temperature range.
4-6. POWER DISTRIBUTION
Primary DC power for the amplifier is provided by the host system. The amplifier
module has a DC/DC converter that converts the +26 Vdc to +15 Vdc, +5 Vdc and
+8 Vdc.
Figure 4-1. NTGS86AA Single Channel Power Amplifier Functional Block
Diagram
SPURIOUS DETECTION
DSP CIRCUIT
RF
IN
Phase,
Gain,
and
Bias
Control
Phase,
Gain,
and
Bias
Control
33dB
Gain
10dB
Gain
Three Stage
Driver
Main Amp
RF
OUT
Optimize
the
spurious
emissions
mask
of the
CDMA
output
signal
ALARM CIRCUIT
